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Show 318 CEREAL PLANTS. CnAP. JX. with peculiar leaves appeared, it would be neglected unless the grains of corn were at the same time superior in quality or size. The selection of seed-corn was strongly recommended 43 in ancient times by Columella and Celsus; and as Virgil says,- " I've seen the largest seeds, tho' view'd with care, Degenerate, unless th' industrious hand Did yearly cull the largest." But whether in ancient times selection was methodically pursued we may well doubt, when we hear how laborious the work was found by Le Contour. Although the principle of selection is so important, yet the little which man has effected, by incessant efforts 44 during thousands of years, in rendering the plants more productive or the grains more nutritious than they were in tho time of the old Egyptians, would seem to speak strongly against its efficacy. But we must not forget that at each successive period the state of agriculture and the quantity of manure supplied to the land will have determined the maximum degree of productiveness; for it would be impossible to cultivate a highly productive variety, unleRs the land contained a sufficient supply of the necessary chemical clements. We now know that man was sufficiently civilized to cultivate the ground at an immensely remote period; so that wheat might have been improved long ago up to that standard of excellence which was possible under the then existing state of agriculture. One small class of facts supports this view of the slow and gradual improvement of our cereals. In the most ancient lake-habitations of Switzerland, when men employed only flinttools, the most extensively cultivated wheat was a peculiar kind, with remarkably small ears and grains.45 "Whilst the grains of the modern forms are in section from seven to eight millimetres in length, the larger grains from the lake-habitations are six, seldom seven, and the smaller ones only four. The ear is thus much narrower, and the spikelets stand out more horizontally, than in our present forms." So again with barley, the most ancient and most extensively cultivated kind had small ears, and the grains 43 Quoted by Lo Contour, p. 16. 44 A. De Candollc, 'Gcogrnph. Bot.,' p. 932. 45 0. IIc01·, • Die Pflanzen de1· Pfahl-buutcn,' ISGG. Tho following passage is quoted from Dr. Christ, in 'Die Fauna der Pfahlbautcn von Dr. Riitimcyer,' lSGI, s. 225. CHAP. IX. WHEAT. 319 were "smaller, shorter, and nearer to each other, than in that now grown; without the husk they were 2~ lines long, and scarcely 1~ broad, whilst those now grown have a length of t~ree lines, and almost the same in breadth." 46 These small-gramed varieties of wheat and barley are believed by Heer to be the parent-forms of certain existing allied varieties, which have supplanted their early progenitors. Hccr gives an interesting account of the fir.st appearan~e and final disappearance of the several plants which were. cultivated in greater or less abundance in Switzerland durmg former successive periods, and which generally differed more or less from our existing varieties. The peculiar small-eared and sm~llgrained wheat, already alludecl to, was the commonest k~nd during the Stone period; it lasted down to th~ HelvetiCoRoman aae aml then became extinct. A second kind was rare at first bu~ afterwards became more frequent. A third, the Egypti~n wheat (T. turgidum), does ~ot agree., exactly ~ith any existing variety, and was rare durmg the Stone pe:wd. ~ fourth kind (T. dicoeeum) differs from all known vanet1es of th1s form. A fifth kind ( T. monoeoeeum) is known to have existed dm·ina the Stone period only by the presence of a single ear. A si~h kind, the common T. spelta, was not introduced into Switzerland until the Bronze age. Of barley, besides the shortcared and small-grained kind, two others were cultivated, one of which was very scarce, and resembled our present common II. distiehum. During the Bronze age rye and oats were introduced; the oat-grains being somewhat smaller than those pr~duced by our existing varieties. The poppy was largely cultlvatcd during the Stone period, probably for its oil; b.ut the variety which then existed is not now known. A peculiar pea with small seeds lasted from the Stone to the Bronze age, and then became extinct; whilst a peculiar' bean, likewise having small seeds, came in at the Bronze period and lasted to the time of the Romans. These details sound like the description given by a palmontologist of the mutations in forrr~., o! the fir~t appearance, the increasing rarity, and final extmctwn of fossil species, embedded in the successive stages of a geological for-mation. 46 Heer, us quoted by Curl Vogt, 'Lectures on Man,' Eng. translut., p. 355. |